ramdisk: Import initial CM 11 ramdisk

Change-Id: Ic4eb69341e92c7525ddf809d3e129c2061d7ba5d
Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
ramdisk: Improve bootup speed

Switch to noop while booting to prevent boot animation jank.
Increase readahead value for row to perform more effectively.

Change-Id: Ie7c2ff5b9ac34dad6ee551dca17e5aacad21c077
Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>